MONTREAL — So much of the Washington Capitals’ success these days depends on the performance of their goaltender. They aren’t generating much offense, opposing teams routinely establish base camps in their zone, and when the margin for error seems minuscule, one save can make all the difference.

That theme was hammered home once again Saturday afternoon at Bell Centre, where the Capitals spent more than 38 minutes of the game clinging to a one-goal lead against the Montreal Canadiens. But when Tomas Vokoun puts forth a flawless effort, it ensures two points are within reach.

Vokoun recorded 30 saves and led the Capitals to a 3-0 win over Montreal after serving as a flotation device until his teammates offered breathing room on the scoresheet with two third-period goals.

The victory marked Vokoun’s first shutout in 21 career appearances against the Canadiens, the team that drafted him in the ninth round in 1994.

“We needed the two points and we play pretty good game,” said Vokoun, who recorded his third shutout of the season. “We play smart and we were fortunate enough to get a one goal lead and play smart road game. . . . Look at the standings, we’re outside the playoffs. We need every point we can get.”

The victory gives Washington 58 points, but the team fell back out of playoff position at ninth in the Eastern Conference when Toronto shut out Ottawa on Saturday night. The Capitals remain in second place in the Southeast Division trailing Florida, which stayed at 59 points when it lost to Tampa Bay.

Turnovers and disjointed plays dominated the contest early, but Washington managed to take a 1-0 lead 8 minutes 10 seconds into the first period when a fluky shot by defenseman Dennis Wideman fluttered past Canadiens backup netminder Peter Budaj, who made 20 saves.

It was a strange shot, similar to one a golfer might chip with a wedge, and far from the usual slap shots Wideman fires from that location on a routine basis.

“The All-Star Game he had a 95 mile-an-hour shot. And once he scored I was like, a 9.5-mile-an-hour one will work too, I guess,” Capitals forward Brooks Laich said of the odd tally. “Sometimes you get lucky; that’s all that was. It was a fluke goal, a lucky goal. But we’ll take it and move on.”

Despite the advantage, Washington was not dominating the Canadiens, who stand in 27th place in the league and are in last in the East.

The Capitals didn’t have a shot on goal closer than 29 feet in the first period. In the second, however, the Capitals mustered only three shots on Budaj from any range.

After killing an early penalty, Montreal, spent most of the middle period in the Capitals’ zone. But as they tried to rally, the Canadiens demonstrated some of the futility that has plagued them this season and ran into a poised Vokoun.

The 35-year-old Czech absorbed the shots they put on net, stood his ground in the face of traffic and appeared to grow more unflappable with each stop. Montreal outshot the Capitals, 10-3, in the second, but with an impenetrable Vokoun serving as the backbone, the visitors entered the intermission with their precious one-goal lead. Washington also still had time to snap back into the game and offer Vokoun more support.

“They came at us really hard there in the second period, but we still came in with a one-goal lead,” forward Matt Hendricks said. “I think that might have taken the wind out of their sails a little bit, then we get the second one [in the third] and you can tell their confidence is dwindling. I thought Vokey was a big reason for that.”

The Capitals rediscovered their energy in the third, and 6:11 into the period Hendricks shot a rebound into a wide-open net to make it 2-0 as Laich created havoc in the crease.

Alexander Semin, who helped set up Hendricks’s goal when he carried the puck into the corner of the offensive zone, recorded a goal of his own on a penalty shot with 11:57 elapsed in the period to make it 3-0. The Russian winger skated into the slot before blasting a slap shot to the top shelf that Budaj had little chance of defending.

As Semin’s shot ricocheted out of the net, it became clear the Capitals were on their way to shutting out Montreal for a third straight game at Bell Centre.

The Canadiens have not scored on the Capitals here for 216:32, or since March 15, 2011, and Vokoun became the third goaltender to hold them at bay during this stretch.

“We were pretty bad there in the second period, they took over the game and they had a lot of scoring chances, a lot of shots, extended shifts in our own zone,” Wideman said. “Vokey stood tall for us, and that gave us a chance to get those extra goals. That was the difference in the game.”

Capitals note: Joel Rechlicz cleared waivers and was reassigned to the American Hockey League’s Hershey Bears.